The present invention relates to a regulated apparatus for the generation of electrical energy, such as a wind generator, comprising driving means consisting of a propeller and a transmission mechanism on whose input shaft the propeller is mounted and whose output shaft is a driving drive shaft, a generator driven by the driving shaft, and means for regulating the speed of rotation of the propeller.
In apparatus of this kind it is necessary both to effect mechanical regulation for limiting the maximum speed and possibly to regulate the driving speed, and to regulate the voltage by acting on the excitation of the generator. It is known to regulate the driving speed by adjustment of variable pitch blades of the propeller, and to regulate the voltage by electronic regulation of the excitation of the generator.
These known procedures have numerous disadvantages. Adjustment of the propeller blades is usually effected by means of an inertia relay, which is liable to failure and is difficult to maintain. Furthermore, an inertia relay is a source of vibrations, and such vibrations destroy the bearings of the windmill. Electronic regulators also require specialized maintenance, so that when a failure occurs there is an unacceptable delay because of the usually isolated situation of the apparatus. Additionally such electronic regulators are very expensive to buy, and not infrequently cost as much as all the rest of the windmill.
A main object of the invention is to eliminate all regulating relays and to provide a simple structure which is easy to maintain. A further object of the invention it to use simple regulation means which makes it possible to select and regulate minimum and maximum speeds, based on a chosen nominal speed.
Yet another object of the invention is to make it possible to drive the aerogenerator at an initial speed as soon as a minimum wind speed occurs after a calm period, which minimum wind speed is lower than the wind speed for starting the propeller, but is sufficient to produce energy at that minimum wind speed.